The present invention relates to a locking mechanism for bracketless extension rods. This invention is particularly suited for use with a flat bracketless extension rod, such as expandable curtain, drapery or closet rods, but is by no means limited to such applications.
The concept of a bracketless rod which can be adjusted for various lengths is well-known. A first rod is inserted (telescope-like) into a larger second rod section, and once inserted, is adjusted to the length desired. Previously, this has been done by anchoring the opposite ends of the first and second rod sections against opposite walls or by using elaborate and complicated locking elements within the rods that may be difficult to install.
One known system for a flat bracketless rod uses two flat plates separated and attached to each other by a spring or biasing means where the first plate is fitted within one rod section. The first plate is adjustably kept in place by two screws and accompanying lock washers which pinch the rolled edges of the rod sections. The second plate, which is attached to the first plate by the spring means, is then inserted into the same rod section where it abuts the end edge of the second rod section fitted within the first rod section. The first plate is locked into place by tightening the screws to pinch the edges of the first rod section. Tension is attained by locking the first plate on the first rod section, so that the overall length of the two rod sections is approximately a half an inch greater than the surfaces between which the rod is to be installed. Subsequently compressing the second, inner section against the second plate will allow the rod to fit between the surfaces. However, it may be cumbersome to install such a rod because of the necessity for properly determining the overall rod length and then to properly screw or tighten the first plate into place.
The present invention utilizes a mechanism which permits for easy adjustment of the extension between the first and second rod sections, and for readily securing the first and second rod sections into place once the sections are at a desired length.